Ballistic and blast resistant panels are well known and take on a variety of configurations for providing armor to buildings, vehicles, ships, airplanes and a variety of other applications where armor is required. Armor should be both ballistic resistant and blast resistant. In addition to typical projectiles, it is also desirous to stop high velocity armor piercing weapons.
Traditional armor is commonly solid metallic armor made of steel, aluminum, titanium or alloys thereof. Such solid metallic armors typically possess excellent stopping power. However, the steel and aluminum metallic armor has several drawbacks, including low weight efficiency compared to composite systems. Titanium systems typically perform better than steel and aluminum, but titanium is expensive. Although solid metal armor does have excellent multi-hit characteristics, metal armor often creates fragment projectiles on the backside of the armor that cause additional dangers. Such fragments may be widely dispersed from the solid armor and can be as dangerous or more dangerous than the initial, primary projectile.
To overcome such shortcomings, composite armors have been developed that are highly weight efficient, offering improved projectile and fragment stopping power per weight as compared to solid metal armors. However, composite armors based on ceramic strike faces with composite backing plates have typically included carbon, glass and aramid polymer composites, which are expensive. Moreover, since manufacturing processes for the ceramic strike faces are slow and power intensive, the resulting armor can be in short supply. Backing plates have heretofore utilized traditional fibers, typically at diameters less than 100 microns. Such fine diameter fibers for low cost, stiff and high elongation thermoplastic polymer systems have limited use, due to the inability to adequately wet the fibers at required high fiber volumes.
Innovations in reinforcements have been made utilizing ultra high strength twisted steel wires. See, for example, U.S. Pat. Nos. 7,144,625 and 7,200,973. Such material, made under the trade name HARDWIRE®, affords users the ability to use material that may be eleven times stronger than typical steel plate as reinforcement for many different materials. The HARDWIRE® material functions as a moldable, high strength steel. The material may be molded into thermo-set, thermoplastic or cementitious resin systems. The HARDWIRE® material can be used to upgrade steel, wood, concrete, rock or other materials and may be retrofit for some applications. Moreover, the inexpensive HARDWIRE® material is typically priced like a glass material, while performing like carbon composites. In addition, such composites may typically be up to 70% thinner and 20% lighter than composites made with glass fibers. The material may be molded so that it can be applied to multiple shapes for various applications.
An armor panel system having a hardened strike face and reinforced backing panel is described in WO 2005/098343. In this system, the hardened strike face may be a material having a high hardness, such as granite, hardened concrete or ceramic tile. The hardened strike face acts to flatten or shatter the projectile and a cone of pulverized material is spread through to the backing panel. The backing panel absorbs and spreads out the material and supports the strike face to resist dilation for improved multi-hit performance. The reinforced backing panel utilizes reinforcement materials having high strength and stiffness, such as the HARDWIRE® material, to provide support to the strike face upon impact. The reinforcement backing may be provided in unidirectional layers that are oriented at, for example, 90° to one another. Staples may extend through the layers to provide additional resistance against delamination.